a) Field of the Disclosure
This disclosure relates to the field of hand tools, specifically hand tools having a clamping portion similar to traditional pliers.
b) Background Art
Hand tools for gripping material and work pieces are commonly utilized devices which are generally known as pliers. Pliers have been formed in a variety of embodiments in the prior art but generally operate on the principle of having a central pivot member between two plier members. Some prior art pliers have the capability to lock the jaw portion of the pliers without constant interaction of the tool handler.
Locking multi-tools using a member under compression such as that disclosed in U.S. Pat. No. 4,318,316 are also fairly common. Locking plier technology has even been applied to folding multi-tools, such as that disclosed in U.S. Pat. No. 6,006,385. This particular patent discloses a locking multi-tool having a toggle link 70 connected to a handle 16 configured to lock about an object by pressing handles 16 and 18 toward each other.
The most common type of locking pliers are found under the trade mark Vise-Grip™, a Registered Trade Mark of Petersen Mfg., Co.'s locking pliers. Petersen is part of American Tool Companies, Inc. Prior art locking pliers are based upon the general principle of placing some form of a cross-linked member in compression so as to apply stored energy to this cross-linked member whereas when this cross-linked member extends beyond some maximum compression point, the spring stored energy will lock the player handles and more particularly the jaw members to a closed orientation. The operating principle behind Vice-Grips is well-known in the art, and of course utilizes some form of a screw adjustment member to adjust the orientation of the jaw members.
Most individuals who are familiar with hand tools are familiar with locking pliers and are likely well aware of the limitations of locking pliers, such as having to adjust the end jaw regions by way of an extendable member, such as a threaded screw, to make the pliers operational for gripping a material or a plurality of materials which are to be clamped together. This process requires the individual utilizing the locking pliers with a prior art-type compression link member to adjust a screw normally at the longitudinal end base region of one of the plier handle members so as to orientate the pliers at an approximate width location, whereby applying a compressive force between the two handle members will lock the jaws upon the material.
Of course one issue with this arrangement is that the locking pliers are generally not capable of being utilized as a regular set of conventional pliers, for example to quickly clamp upon a variety of sizes of materials without necessarily adjusting the orientation of the compression cross-link member. In other words, conventional pliers having a jaw region, each connected to corresponding handle regions, can open wide and narrow to accommodate a variety of tasks for quickly clamping upon various sized materials such as bolts, rods, etc. However, conventional types of pliers, as well as conventional non-locking multi-tools, generally do not have any sort of locking capability to remain intact upon a material when the handle members are no longer grasped.
Further, the locking member folding tools such as that introduced above in U.S. Pat. No. 6,006,385 utilize the prior art technology of an intervening compression link member and require a plurality of procedures and limitation for utilizing the pliers as a conventional non-locking plier.
A new technology such as the locking plier entitled Auto-Lock distributed by Sears Craftsman discloses a plier which is automatically adjusting with regard to the width of the jaw members, but when tension is applied to the jaw members, an internal mechanism will become substantially fixed to provide a locked point for the compression member to act upon the handles. This design does indeed provide the flexibility of self-adjusting locking pliers, but requires many components and provides a compression member to have the stored energy be supplied therein for locking the jaw members together.
Therefore, as described herein, there is a novel concept of utilizing a linkage member which is in tension and which can apply a closing locking force upon the first and second jaw members. This novel design can be carried out in a plurality of embodiments shown herein wherein the embodiments have different operational benefits depending upon the intended use. In one form, the tool is a multitool where the handle members can fold and be positioned around the jar region for a compact design. In this form, other tool members can be positioned within the handle or both of the handles of the multitool. Other forms are shown herein such as a conventional set of tension pliers which can be foldable or be a fixed type of design.
Further disclosed herein are various adjustment mechanisms to adjust the tension member to accommodate a plurality of sized materials positioned interposed between the first and second jaw members. As will be described further herein, this adjustment system requires an adjustment of the effective portion of the tension member, and in some cases the attachment locations of the tension member with respect to a center locking pivot of the tension member, which will be described thoroughly herein.